Contours are not projected, but are provided in geographic coordinates (latitude and longitude) in units of decimal degrees, and horizontally referenced to the North American Datum of 1983. Contour elevation values are vertically referenced to the North American Vertical Datum of 1988. Contours are staged in Esri File Geodatabase 10.1 or Shapefile format, and distributed in 1x1 degree tiles.
Related Content
Are depression contours identified in 3D Elevation Program (3DEP) contour products?
Yes, depression contours are identified with tick marks in 3D Elevation Program products, but only in large scale contours (1:36,000 scale to 1:18,000 scale).
What geographic areas do 3D Elevation Program (3DEP) contours cover?
3D Elevation Program (3DEP) contours cover all of the United States and its territories at multiple scales: Small scales (1:578,000-1:289,000) Medium scales (1:144,000-1:72,000) Large scales (1:36,000-1:18,000) Contours are easily viewed in The National Map Viewer and USGS topographic maps, or downloaded through The National Map Download Client. Learn more: Map Scales
What is the difference between lidar data and a digital elevation model (DEM)?
Light detection and ranging (lidar) data are collected from aircraft using sensors that detect the reflections of a pulsed laser beam. The reflections are recorded as millions of individual points, collectively called a “point cloud,” that represent the 3D positions of objects on the surface including buildings, vegetation, and the ground. Digital elevation models (DEMs) are one of many products...
Are 3D Elevation Program (3DEP) contour lines updated and what sources were used to create them?
When significant changes in the landscape have occurred, contours will be updated on an as-needed basis. The 100-foot contours were derived from 3DEP (formerly National Elevation Dataset) one arc-second resolution data that was sub-sampled to a cell size of three arc-second. The 50-foot contours were also derived from one arc-second data. Large-scale contours were derived from 1/3 arc-second...
The National Map—New data delivery homepage, advanced viewer, lidar visualization
The 3D Elevation Program—Flood risk management
3D Elevation Program—Virtual USA in 3D
USGS lidar science strategy—Mapping the technology to the science
Related Content
- FAQ
Are depression contours identified in 3D Elevation Program (3DEP) contour products?
Yes, depression contours are identified with tick marks in 3D Elevation Program products, but only in large scale contours (1:36,000 scale to 1:18,000 scale).
What geographic areas do 3D Elevation Program (3DEP) contours cover?
3D Elevation Program (3DEP) contours cover all of the United States and its territories at multiple scales: Small scales (1:578,000-1:289,000) Medium scales (1:144,000-1:72,000) Large scales (1:36,000-1:18,000) Contours are easily viewed in The National Map Viewer and USGS topographic maps, or downloaded through The National Map Download Client. Learn more: Map Scales
What is the difference between lidar data and a digital elevation model (DEM)?
Light detection and ranging (lidar) data are collected from aircraft using sensors that detect the reflections of a pulsed laser beam. The reflections are recorded as millions of individual points, collectively called a “point cloud,” that represent the 3D positions of objects on the surface including buildings, vegetation, and the ground. Digital elevation models (DEMs) are one of many products...
Are 3D Elevation Program (3DEP) contour lines updated and what sources were used to create them?
When significant changes in the landscape have occurred, contours will be updated on an as-needed basis. The 100-foot contours were derived from 3DEP (formerly National Elevation Dataset) one arc-second resolution data that was sub-sampled to a cell size of three arc-second. The 50-foot contours were also derived from one arc-second data. Large-scale contours were derived from 1/3 arc-second...
- Multimedia
- Publications
The National Map—New data delivery homepage, advanced viewer, lidar visualization
As one of the cornerstones of the U.S. Geological Survey’s (USGS) National Geospatial Program, The National Map is a collaborative effort among the USGS and other Federal, State, and local partners to improve and deliver topographic information for the Nation. The National Map is featuring direct links to new and improved GIS data access utilities on a refreshed data delivery homepage at https://wAuthorsThe 3D Elevation Program—Flood risk management
Flood-damage reduction in the United States has been a longstanding but elusive societal goal. The national strategy for reducing flood damage has shifted over recent decades from a focus on construction of flood-control dams and levee systems to a three-pronged strategy to (1) improve the design and operation of such structures, (2) provide more accurate and accessible flood forecasting, and (3)AuthorsWilliam J. Carswell,, Vicki Lukas3D Elevation Program—Virtual USA in 3D
The U.S. Geological Survey (USGS) 3D Elevation Program (3DEP) uses a laser system called ‘lidar’ (light detection and ranging) to create a virtual reality map of the Nation that is very accurate. 3D maps have many uses with new uses being discovered all the time.AuthorsVicki Lukas, J. M. StokerUSGS lidar science strategy—Mapping the technology to the science
Summary The U.S. Geological Survey (USGS) utilizes light detection and ranging (lidar) and enabling technologies to support many science research activities. Lidar-derived metrics and products have become a fundamental input to complex hydrologic and hydraulic models, flood inundation models, fault detection and geologic mapping, topographic and land-surface mapping, landslide and volcano hazardsAuthorsJason M. Stoker, John Brock, Christopher E. Soulard, Kernell G. Ries, Larry J. Sugarbaker, Wesley E. Newton, Patricia K. Haggerty, Kathy Lee, John A. Young - News